TOST vs. Schweizer Hooks on Tow Planes.

Originally Posted by

Mr. Connelly, for my own knowledge where does the 1500/1200 lb. limitation on the Schwiezer system come from. Ive tried to find a reference in the past but couldnt find one.

To respectfully add to the debate, I'd challenge anyone in favor of ousting the Schwiezer system if they feel the same way about aero tow with a Tost c.g. hook? Here the superior Tost system has been perhaps miss used and this installation has caused more glider accidents and fatalities than Schwiezer release on tow plane accidents.
I appreciate the position of the "hands off" crowd, what I'd like to see is if those in favor of banning the Schwiezer system on the tow plane also believe they should be beholden to a regulation or policy affecting the method by which they are towed in their glider (when it's their expense).
These two items would have the single biggest impact on soaring safety that I can think of at the lowest cost and highest participation level if it were either a regulatory or insurance requirement. The problem is pilots are cheap and nobody thinks it will happen to them.

-Doug

The Schweizer hook is limited to a 1200 lb rope which by the 80-200 rule would limit the max gross weight of the glider in tow to 1500 lbs. This came from the Schweizer factory recommendations. You could use a stronger rope but would have to then use a weak link of appropriate strength. I believe the Tost system has a limit of 900kg which is just short of 2000 lbs covering most all current gliders. Any supplier should be able to supply you with the pertinent published limitations. Wings and Wheels would be a good source.

I don't follow you on the Schweizer vs Tost system regarding accidents. I have not seen those statistics, perhaps you could site them? I will say that in 7000 tows I have never had a problem with a CG hook glider but then again most of these are flown by more experienced pilots. It will be the student on solo or occasionally an older pilot who should no longer be flying who will upend you.

Walt Connelly

You don’t mention what type of fleet you have. Putting a Tost tow hook on a Pawnee, Super Cub or Husky is very simple mechanically and paperwork wise.